Sling and method of making same



Nov. 4, 1947. 1. R. MITCHELL 2,430,071

SLI'NG ANdMETHOD OF MAKING SAME Filed March 9, 1946 v 2 She ets-Sheet 15 I I! I1 I V 4; Q 4- 4 v n INVENTOR I. R. MITCHELL R/VEY 2 Sheets-Sheet2 H T 2 N 0 E .1 C VT T Wm A I. J Y 5 SLING' AND METHOD OF MAKING SAMENov. 4, 1947.

Patented Nov. 4, 1947 UNITED STATES PATENT OFFICE SLING AND METHOD OFMAKING SAME Irvin R. Mitchell, St. Louis, Mo., assignor to A. Leschen &Sons Rope Company, St. Louis,

Mo, a corporation of Missouri Application March 9, 1946, Serial No.653,394

(o1.-s7-s Claims.

- forming the sling from a single piece of material which I manipulatein a novel manner to form the sling, instead of forming it in the mannercommon to rope slings heretofore .made. erally in braiding a slinghaving any reasonable multiple of four members, a twist develops'in thebraided members, and in order to get the twist out it is necessary atintervals to reverse the direction of braiding, which leaves short,unbraided sections in the braided material, known as cross-overs. Iovercome this by weaving the sling from the center, through which I getmore equal weaving without any twist, so that through my invention thematerial is woven in a manner not heretofore practiced in the art, whichautomatically eliminates the twisting tendency and avoids cross-overs.

The present invention differs from other rope slings in the method ofweaving, or braiding, or plaiting. For convenience I have illustratedand will describe an eight member device. It consists of manipulating asingle length of material so.

as to form eight members, which are separated into four pairs, and whenthese have been manipulated into a certain position, the remainder ofthe operation is performed from the center in opposite directions insuch a manner as to weave both ends of the sling at the same time, andthen the material is locked in this posi tion with two temporary pinsand then the two free ends of the material are unwoven to thesling-center, just past the locking pins, reinserted through the slingbody, which looks them through the center, and then they are rewovenback into the sling.

Another important advantage of my invention is that through its use thesling attains theform of a flexible, cohesive unit, and the capacity ofthe eight strands of material which form the sling is very little lessthan the aggregate capa-- city of eight separate units of the material.

In the drawings- Fig. 1 illustrates a single length of material coiledbefore the weaving of the sling is commenced.

Fig. 2 illustrates'the separation and grouping of the members justprior'to the commencement of the weaving operation.

Figs; 3 and 4 illustrate the first two repetitive steps in th weavingprocess.

Figs. 5 and 6 illustrate the method of looking I the weave of theassembly, just prior to the insertion of the temporary locking pins atthe center.

Figs. 7 and 8 illustrate the preferred treatment of the free ends of themembers.

Fig. 9 illustrates the manner of holding the woven members fromunweaving by the insertion of two temporary locking pins. v

The method of forming a sling as herein illustrated and describedapplies to any reasonable multiple of four members. For convenience ofdescription, I preferably show eight members which clearly illustratesmy method of weaving.

The invention preferably comprises a singl length of material, of asingle unit or a number of units, having two free ends A and B. Thefirst step in the manipulation consists in coiling the materialpreferably to form eight parallel members l to 8, inclusive, with theends A and B extending beyond the same end of the coil, as illustratedin Fig. 1. The eight members are then separated to form four pairs, orgroups, 9, H), H, and I2, respectively, as illustrated in Fig. 2. Assumethat the flat plane of the coils is relatively horizontal. In Fig. 2 thegroups or pairs I0 and II are in a horizontal plane, and the groups orpairs 9 and I! are in a vertical plane. It is preferred that the membersor groups 9 lead from opposite sides of the end loops, and likewise themembers ofthe pair or group I2 lead from opposite sides of the endloops. However, as also pre-- ferred, the members of the pair or groupI0 lead from the same side of the end loops, and themembers of the pairor group H also lead from the same side of the end loops. The free endsA and B are in opposite pairs in the same plane.

The pairs or groups 9, It, H, and 12 are now progressively manipulatedas shown in Figs. 3

and 4. It is preferred to do it by first crossing one of the horizontalpairs through its opposite horizontal pair, then crossing one of thevertical pairs through its opposite Vertical pair. process is repeatedas to horizontal and vertical sequence until weaving is completed. Thiscontinued sequence produces a better appearing sling. When the pairs orgroups 9, I0, I i, and 12 have assumed the position illustrated inFig-.4,

This 7 3 the weaving of the sling is continued by repeating theoperation illustrated in Figs. 3 and 4, by weaving the pair 1 I throughthe pair Ill, then weaving the pair l2 through the pair 9. It is to beunder stood that the weaving of the respective pairs 9 and I2 througheach other may be reversed, if desired. It is preferred that the weavingoperation be as shown in Figs. 3 and 4, but this might also beaccomplished by passing any one pair between the members of any oppositepair in the same plane. This might also be accomplished by passingopposite pairs or groups of members in the same plane past each otherinstead of through each other. The weaving is continued until the centerof th sling is reached, as illustrated in Fig. 5, and as compact as isdesired by the operator, when it will have a multiplicity of nodes I3.At this time the Weaving is completed. Then the Weave is temporarilylocked by inserting two pins 16 and I! to retain all pairs in such lastwoven position.

At this point the free ends A and B are unwoven to the sling center, orjust a short distance past the center, and past the two pins [6 and IT,as shown in Fig. 6, their paths being marked by inserting tracers (notshown). The free end A is unwoven to the center or a little past thecenter and past pin l6 (Figs. 5 and 6), inserted through the openingformed by the locking pin I6 that had been adjacent to A, and is thenrewoven back into the sling body in the path formerly occupied by theend B. Likewise, the free end B is unwoven to the center or a littlepast the center of the sling and past pin I! (see Figs. 5 and 6),preferabl inserted through the opening formed by the locking pin I! thathad been adjacent to B, and is then re-woven back into the sling body inthe path formerly occupied by the end A. When the end A has beenre-inserted into the sling next to temporary locking pin I6, and the endB has been re-inserted into the sling next to temporary locking pin [1,both pins may then be withdrawn from the sling as the ends A and B arenow the permanent locking members for preventing the unweaving of thesling. At this point-the free ends A and B have reversed theirpositions, as illustrated in Fig. 6. The free ends A and B may now besecured in any one of various ways. The method illustrated in Figs, '7and 8 is the preferred form, which is carried out as follows: i

In a manner that is customary in the art, the free end A is now splicedinto the body of the end B, as shown at the point I4, and securedtightly in position, and the free end B is looped and inserted, ortucked, into the sling at the point where the sling body commences. Thesling has now assumed the position shown in Fig. 8, preferably havingcomplete end loops l5 and [6, respectively.

From the above it will be obvious that my method of weaving does not putany twist into the members and therefore it is not necessary to take outany twist, therefore there are no "crossovers. An equal tension isplaced upon the members throughout all parts of the sling, andthemembers in one end thereof will have the same tension as the members inthe opposite end,

By having the locking sectionat the longitudinal center of the sling, itis my belief that I thereby provide an equalizing section for absorbingall or any unequal strain or strains that might develop during the useof the sling.

I claim:

1. The method of forming integrally from a,

4 single length of material a flexible sling, which consists in coilingsaid length of material into a plurality of straight parallel portionsand connecting end sections, said coiling providing two free ends of thecoiled material, grouping said straight portions into a plurality ofpairs, the two free ends being at the same end of the coil, weaving saidpairs together from the center, unweaving said two free ends to thecenter of the sling and reinserting them back into the woven structurein such manner as to securely lock the weave, and returning said freeends back to the same end of the coil they occupied before they wereunwoven.

2. The method of forming integrally from a single length of material aflexible sling, which consists in coiling said length of material into aplurality of straight parallel portions and connecting end sections,said coiling providing two free ends of the coiled material, groupingsaid straight portions into a plurality of pairs, the two free endsbeing at the same end of thecoil, weaving said pairs together from thecenter, unweavin said two free ends to the center of the sling andreinserting them back into the woven structure in such manner as tosecurely lock the weave, returning said free ends back to the same endof the coil they occupied before they were unwoven, and splicing saidtwo free ends into the sling.

3. The method of forming integrally from a single length of material aflexible sling, which consists in coiling said length of material into aplurality of horizontal, straight, parallel portions and a plurality ofconnecting end sections, separating said straight portions into aplurality of groups of pairs in horizontal and vertical planes,respectively, weaving said horizontal and vertical pairs together fromthe center, locking the completed weave at the center and providing asection at the center of the sling to equalize any unequal strains thatmight develop during the use of the sling.

4. The method of forming a flexible sling of a single length ofmaterial, which consists in grouping said material into eight membersand again dividing said members into four pairs with the free ends ofsaid length of material extending beyond the same end of said sling,simultaneously interweaving the four pairs of the sling, unweaving thefree end portions of said material approximately to the center of saidsling, passing said free ends through the center of said sling so as tolock the weave, re-weaving said end portions back into said sling, andsecuring the free ends of said members.

5. A flexible braided sling comprising four groups of members interwovenand permanently locked at the sling center, and having two end portionsterminating at one end of said sling, said two end portions being incrossed position at the sling center so that each of said two endportions occupies the path originally occupied by the other of said twoend portions through half the length of the sling.

IRVIN R. MITCHELL.

REFERENCES CITED The following references are of record in the file ofthis patent.

UNITED STATES PATENTS Number Name Date 1,901,439 Drew Mar. 14, 19332,142,6 i1 Garris Jan. 3, 1939

